1. Field of the Invention
The present invention relates to a fuel supply device which houses a fuel pump and a fuel filter in a sub-tank and is mounted within a fuel tank for an internal combustion engine.
2. Related Art
As a fuel supply device, JP-A 3-67058 proposes one type which houses a fuel pump within a sub-tank to maintain fuel in the sub-tank and enable the fuel pump to suck the fuel even when fluid in a main fuel tank decreases.
This type of fuel supply device is required to be as compact in size as possible to meet a recent trend to reduce in size any component parts mounted in a vehicle. Particularly when the main fuel tank is made of resin, the main fuel tank should have a sub-tank mounting hole as small as possible not to lower the rigidity and sealing performance of the fuel tank. Thus, the fuel supply device including the sub-tank and other component parts arranged outside of the sub-tank should be reduced in size as much as possible for facilitating mounting of the same through the sub-tank mounting hole, without reducing a volume of the sub-tank. Further, more component parts should be integrated into a module to facilitate assembling of the fuel supply device.